Is what's taught in B-schools relevant for founders?

Hesser: In a class, you look at case studies, which have a survivorship bias. When you're building a business, there's so much uncertainty. Navigating that is the most important skill--and one you get only in the real world.

Gilboa: It gives you a solid understanding of core fundamentals. But the most important skills taught are softer: organizational design, giving and receiving feedback, managing people--which often aren't taught to someone coming up in their career.

Is business school a waste of time? You could be starting a company.

Hesser: We'd spent time in our industry, and knew the opportunities and flaws. I don't think we would have understood them in a deep way without that experience.

Gilboa: A lot of people use B-school the way I did, to explore ideas and see which have the best chance of succeeding. Warby Parker would not exist without B-school.

Are business schools still the best place to network?

Hesser: I built my network in the food industry--it made a lot of things much easier. An MBA gives comfort to investors, especially if you're a woman. I thought about getting one, but that would have played into prejudices that I didn't think should exist.

Gilboa: Before B-school, I sent emails to CEOs and VCs to see if we could get coffee. I didn't have a great response rate. When I was at Wharton, every person I reached out to responded.

What's more important: industry knowledge or business skills?

Hesser: To me, domain expertise is by far the most important thing you can get in the early part of your career if you want to start a business.

Gilboa: When we talked to industry experts, they'd tell us why our idea wouldn't work. If we had had jobs, it would have been easy to abandon the idea.

Advantage: Hesser

According to Financial Times survey data from 2017, fewer than 20 percent of 2014 business school alums in the U.S. had started a company, and the rate of entrepreneurship for grads has dropped at many top B-schools in the past year.